[Unix; common] To expand special characters in a wildcarded name, or
the act of so doing (the action is also called globbing). The Unix conventions for filename
wildcarding have become sufficiently pervasive that many hackers use some
of them in written English, especially in email or news on technical
topics. Those commonly encountered include the following:

wildcard for any single character (generally read this way only at the
beginning or in the middle of a word)

[]

delimits a wildcard matching any of the enclosed characters

{}

alternation of comma-separated alternatives; thus, ‘foo{baz,qux}’
would be read as ‘foobaz’ or ‘fooqux’

Some examples: “He said his name was [KC]arl” (expresses
ambiguity). “I don't read talk.politics.*” (any of the
talk.politics subgroups on Usenet). Other examples
are given under the entry for X. Note that glob
patterns are similar, but not identical, to those used in
regexps.

Historical note: The jargon usage derives from glob, the name of a subprogram that expanded
wildcards in archaic pre-Bourne versions of the Unix shell.